Process for preparing peptide products for promoting cholecystokinin secretion and use of the peptide products

Abstract

A process for producing a peptide product having cholecystokinin secretion promoting effect, said process comprising hydrolyzing soybean residues with one or more proteases so that the peptide product having cholecystokinin secretion promoting effect is obtained. Also disclosed is the composition containing the peptide product and the use thereof.

1. A process for the preparation of a peptide product for promoting secretion of cholecystokinin (CCK), comprising the following steps:
 (a) mixing a soybean residue with water; 
 (b) hydrolyzing the mixture obtained in step (a) with a protease at a suitable temperature; 
 (c) making the protease in the hydrolysate obtained in step (b) inactive; 
 (d) separating the liquid from the solid of the mixture of step (c) and collecting the liquid so as to obtain the peptide product, 
 
       wherein the soybean residue is obtained by mixing defatted soybean powder with water, adding  Aspergillus sojae  to the mixture to make it ferment and hydrolyze, and removing the liquid from the fermented and hydrolyzed mixture, and wherein the peptide product comprises the peptides of SEQ ID NO:s: 1-43. 
     
     
       2. The process according to  claim 1 , wherein the water is about 0.5 to about 10 times the weight of the soybean residues. 
     
     
       3. The process according to  claim 2 , wherein the water is about 1 to about 5 times the weight of the soybean residues. 
     
     
       4. The process according to  claim 3 , wherein the water is about 3 times the weight of the soybean residues. 
     
     
       5. The process according to  claim 1 , wherein the protease is an endoprotease, an exopeptidase or the combination thereof. 
     
     
       6. The process according to  claim 5 , wherein the protease is Alcalase. 
     
     
       7. The process according to  claim 5 , wherein the protease is in an amount of about 10,000 I.U. to about 125,000 I.U. per kilogram of the soybean residues. 
     
     
       8. The process according to  claim 6 , wherein the protease is in an amount of about 20,000 I.U. to about 125,000 I.U. per kilogram of the soybean residues. 
     
     
       9. The process according to  claim 1 , wherein the mixture is treated with the protease at about 30 to about 60° C. for about 1 to about 24 hours. 
     
     
       10. The process according to  claim 6 , wherein the mixture is treated with the protease at about 30 to about 55° C. for about 1 to about 16 hours. 
     
     
       11. The process according to  claim 1 , further comprising step (e) where the liquid collected from step (d) is concentrated and/or dried so that a concentrated and/or dried peptide product is obtained. 
     
     
       12. The process according to  claim 11 , wherein the liquid is dried by spray drying. 
     
     
       13. A method for promoting secretion of CCK in a subject in need thereof comprising administering an effective amount of the peptide product obtained by the process of  claim 1  to the subject. 
     
     
       14. The method according to  claim 13 , wherein the secretion of CCK inhibits the appetite of the subject.